1. Field of Invention
The present invention relates to an electrical generator, and more particularly to a power generating device which is capable of generating electricity by using energy stored in sea waves.
2. Description of Related Arts
Water constitutes approximately 70% of the entire Earth. Thus, the technology in utilizing energy stored in the sea has becomes a recent research topic all over the world. The sea contains huge amount renewable energy in the form of wave power. However, this form of renewable energy is very unstable and unpredictable. Moreover, collecting such unstable form of energy can be very slow as compared with collecting other form of energy.
Conventionally, there exist three types of wave power devices for capturing wave power and converting the wave power into electrical power. The first type is apparatuses for capturing wave energy through fluid compression. In this type of wave power devices, a predetermined container device is utilized for being immersed into sea water at a predetermined depth. The container device is communicated to the sea water so that a predetermined amount of sea water can flow into the container device. When waves are generated, the water level of the sea fluctuates and this makes the volume of air in the container device fluctuate as well and this essentially compresses the air stored in the container device. The compressed air is arranged to drive a power generator which convert the potential energy stored in the compressed air into electrical energy. This type of wave powers devices have been developed and used in China and Japan. The second type of wave power devices is that of a mechanical type. For this type of wave power devices, sea wave motions are used to drive relative movement of mechanical components for generating electrical energy. The third type of water power devices guides water to flow into contracted water pipelines and utilize the potential energy of the water to drive a turbine for generating electricity. For these types of wave power devices, a common disadvantage is that the conversion efficiency is fairly low. This is because sea waves have to be guided to through many mechanical and electrical components before the wave power can be captured and converted into electrical power. Moreover, since the wave power devices must be built near along the shoreline, the entire power generating structure will be very expensive. The question as to how to develop a wave power device which is capable of efficiently and effectively converting unstable and low-density wave power into electrical power has become a main topic.